The fact of isolationism and they had already purchased Hawaii and Alaska, the manifest destiny was about moving west, when you are too far west you can’t go west or else your drown in Pacific Ocean
<span>it arrived on 10th April 1912
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Because Japan refused to surrender causing the Pacific war to drag on and the United States offered a unconditional surrender known as the Potsdam declaration and said if they didn’t agree to it they would face the alternative of prompt and utter destruction and Japan ignored it